ECLIPSE - TOTAL SOLAR

CEDUNA &amp WIRRAMINNA - SOUTH AUSTRALIA 2002

After deciding at Pt Augusta, we ended up at Wirraminna. For the four of us we agreed
it was spectacular especially all being virgins. I have placed some comments on the eclipse in the December Newsletter and will add them
here when they are done.To receive our Newsletter contact us via the link at the bottom
of the page.

- The Moon will cover 7/8 (88%) of the Sun in Adelaide
- Travel North West from Adelaide for increased totality
- Getting up higher is better and keep the South West Clear
- Use Eclipse Glasses for observing the Eclipse

- Eclipse Glasses can be ordered Ph: 08 8381 3188Small-$5 Large-$8
*Please note - Our Solar Eclipse Glasses are certified and approved safe by German, British
and American Standards. These glasses have not been tested for certification in Australia*

WEDNESDAY DECEMBER 4th (AUSTRALIA)

The Total Solar Eclipse in South Australia on Wednesday the 4th of December
2002 can be seen at its best from Ceduna and Wirraminna (west of Woomera)
in South Australia.
A Partial Eclipse can be seen from the major Australian cities
with Adelaide being the best.

If you've seen a Partial Solar Eclipse, then the main event is yet to be seen!

For a solar eclipse to occur, a 'New Moon' must be between us and the Sun. Normally, the Moon can only be
seen because of the Sun reflecting off the Moon's
surface. A New Moon cannot be usually seen because the
Sun is somewhere behind it.

Diagram of a Solar Eclipse

The two most common and best locations to view the eclipse will be from Ceduna or west of Woomera at
Wirraminna (see map at bottom). Totality time will
decrease and also the height above the horizon will also decrease
as the observer travels east by north east. As a comparison between Ceduna and
Wirraminna, the totality time will be reduced by around 6 seconds and the height above the horizon
will be reduced by around 3 degrees. If there are clouds above the
coastal town of Ceduna there won't be
any chance to make a dash east by north east since there are no roads which lead that way. This part of Australia
is very
desolate and between the two towns, further toward Wirraminna, are very large salt lakes which
are usually dry, but if driven on, a vehicle may get bogged even if
its a 4x4.

A decision needs to be made whether the observer goes for the Ceduna site or the Wirraminna site. Pros
and Cons:

CEDUNA

Eclipse is higher in the sky (3 degrees)

Totality is longer (6 seconds)

Greater chance of clouds

More amenities

More people

Around 800km from Adelaide I'll be there! :-)

WIRRAMINNA

Lower in the Sky (3 degrees), but a higher vantage point can be obtained

Shorter totality (6 seconds)

Less chance of clouds

More sites to see: Flinders Ranges, escaped refugees etc.

Less amenities

Less people

Around 600km from Adelaide

The first sign of the eclipse, for viewers around the Ceduna area, will be on the western side of the Sun at around
6.40pm Ceduna time ACST (Australian
Central Standard Time during Daylight Savings). The same will
be for Wirraminna observers around a minute later. This is called first contact.

As the Sun is half covered, the sky changes to an unusual gun metal grey colour. The darkness in the western
half of the sky is predominate. The Earth gives
up its heat as it is no longer being heated by the Sun. This causes
a slight breeze due to the air cooling faster than the Earth.

Sun Half Eclipsed
(Eastern Sky)

Approaching Totality

As totality fast approaches, the atmosphere is as though a huge thunder storm is approaching, but with
no noise!

Just before totality, the Sun has many bright lights or beads near its edge. This is because of the mountains,
hills and valleys around the edge of the
Moon with the light shining between them. This is called "Baily's
Beads". The last of the Baily Beads visible is called the Diamond Ring Effect (the last
Baily Bead being
the diamond and the corona of the Sun around the Moon being the ring). During a Total Solar
Eclipse, the ring part of the Diamond Ring Effect may not be seen due to the Sun being totally
covered.

Also, just before totality, better if you have a high vantage point, the Moon's shadow can be seen racing
along the ground towards the observer from the direction
of WSW (west by south west).

As the Diamond Ring disappears, this is called Second Contact.

Not Quite The Diamond Ring Effect

During totality, with the magnification of a telescope or similar,
the Sun's prominences can be seen due to the glare of the Sun taken away by the Moon.
The prominences reach tens of thousands of
kilometers or more into space around the Sun. The dark disc of the
Moon replaces the Sun's bright place in the sky. At this
point the brighter stars and planets can be seen.

Two Photographs of a Total Solar Eclipse showing the Sun's Corona

As the Sun reappears from behind the Moon it is called Third Contact. Time to avert your eyes. The western
sky is now brighter, and the eastern sky now
darker.

The Sun and Moon will be setting together in a Partial Eclipse.

IMPORTANT POINTS FOR OBSERVING THE ECLIPSE

OBSERVING:

Get up high if you can.

Know where WSW (west by south west) is for the Moons
shadow rapidly approaching.

The Sun will be fairly low in the sky so make sure the western horizon is clear.

SAFETY

Looking at the Sun even for a few seconds can cause irreversible damage.

Using filters in the eyepiece are dangerous because the heat is concentrated on the eyepiece. One crack....
possible blindness.

During totality, and only during totality, it is safe to view the eclipse with the unaided eye. Eyes should
be immediately averted as the Diamond Ring
Effect (first hint of Sun reappearing) appears once again.

TECHNIQUES
Using a pinhole in a piece of cardboard so that the Sun's image can be projected through the pinhole onto
the white cardboard.

The effect of an eclipse on tree leaves is fascinating. The small gaps in the trees allow light to get through
and act as a pinhole projector (see above).
The effect shows hundreds of little crescents, mimicking the eclipse, projected from
the the image of the eclipse.

A welder's filter No. 12-14 can be used safely to view the eclipse.

TELESCOPES FOR ECLIPSES
Filter caps which fit over the end of your telescope are available.
Let us know your telescope diameter.

Solar projection onto a piece of cardboard or similar is a good way to view the Sun Spots and eclipse. If your
using a large reflecting telescope only use a
small hole to gather the light. A cheap eyepiece like Huygen
(Hoi-gen) or Ramsden are best. They do not use glue to hold the lenses together inside the eyepiece
(it
will melt!). We have them available.

Remember to place a filter over the finderscope of your telescope or block it off all together to prevent
eye damage from the curious wondering what your
looking at. Also, the finderscope can cause a burn and
in some plastic cases - melt!

Its unusual thing that the Sun being so far away and its immense size, compared to the
Moon's relative closeness and small size, has the same diameter disc when observed by us.

Every now and then the Earth, Sun and Moon are almost exactly in line in space. When this occurs, either the Sun or Moon is eclipsed. A solar eclipse (eclipse of the Sun) occurs when the Moon moves directly into line between the Sun and the Earth. The circle of the Moon blocks out the Sun. If the Sun is completely covered, the Earth darkens and we call this a 'Total Eclipse of The Sun'. Its not very often this happens. Most eclipses have only part of the Sun covered and these are called 'Partial Eclipses'.

A Total Solar Eclipses can last up to around 7.5 minutes and the Moon's shadow which is cast upon us can be as wide as 285 kilometers in diameter. A Total Solar Eclipses give astronomers a chance to study the solar corona or outer atmosphere of the Sun which has jets, loops, or more commonly, prominences. The only other way this can be done is by a coronagraph, invented in the 1930's, which mimics an Total Solar Eclipse, removing the blinding glare of the Sun (photosphere).

Due to the fear caused by eclipses in primitive societies, records were kept of when they would occur. This was first done by the Babylonians. The regular cycle of eclipses was names 'Saros' by the Greeks and was found to be 18 years, 11 days and is caused by the Moon's eccentric motion round the Earth.

THE SUNSPOTTER
Your whole class can now observe and follow the storms that play havoc with our tiny globe! Sunspotter gives your students the opportunity to track sunspots as they appear, move and vanish. A bright 3" (76mm) solar image is projected in all its glory by the powerful (2.5") 62mm diameter objective lens. Students can easily trace the face of the Sun and compare it from hour to hour and day to day. Easily aligned to the Sun in Seconds, the Sunspotter makes our closest star a subject of study by even the youngest students, without the complication of telescopes, solar filters and tripods.

This unique, wooden, folded Keplerian telescope provides a much safer and convenient way to view the brilliant light of the Sun compared to more common methods. By using a series of mirrors, the device projects an image of the Sun onto a white viewing screen. Unlike other ways of viewing the Sun, the compact and sturdy Sunspotter is convenient, easy to set up, lightweight and fun to use.

The Sunspotter is also a great way to view solar eclipses in complete safety.
Please inquire for more information and prices.

Black Polymer Solar Viewing Glasses $5AUD

Telescope Solar Filters

AUSTRALIA AND THE PATH OF THE TOTAL SOLAR ECLIPSE OVER
CEDUNA AND WEST OF WOOMERA AT WIRRAMINNA